Continuous Flow Removal of Anionic Dyes in Water by Chitosan-Functionalized Iron Oxide Nanoparticles Incorporated in a Dextran Gel Column

Abstract

This paper describes a novel chromatographic method for efficient removal of anionic dyes from aqueous solutions. Chitosan-coated Fe3O4 nanoparticles can easily be immobilized on a dextran gel column. Single elution of Evans Blue (EB) solution to the nanoadsorbent-incorporated columns provides high removal efficiency with a maximum adsorption capacity of 243.9 mg/g. We also investigated the influence of initial concentration and solution pH on the removal efficiency of EB. The electrostatic interaction between the adsorbent surface and negatively charged sulfate groups on EB molecules promotes the efficient adsorption of dyes. The equilibrium data matched well with the Langmuir isotherm model, which indicated monolayer dye adsorption onto the adsorbent surface. To extend the application of the current method, we performed further adsorption experiments using other anionic dyes of different colors (Cy5.5, Acid Yellow 25, Acid Green 25, and Acid Red 1). All of these molecules can efficiently be captured under continuous flow conditions, with higher removal efficiency obtained with more negatively charged dyes. These findings clearly demonstrate that the present approach is a useful method for the removal of anionic dye contaminants in aqueous media by adsorption.

Iron Oxide/Chitosan Magnetic Nanocomposite Immobilized Manganese Peroxidase for Decolorization of Textile Wastewater

“…Interestingly, nanoparticles have emerged as an efficient tool to generate excellent support for enzymes offering various advantages. Benefits include the ability for a quick biomaterial recuperation using an external magnet, the higher amount of binding enzymes offered by magnetic iron oxide nanoparticles, the low operation price, and the reduction of both fouling and diffusion problems [23][24][25][26][27][28][29]. The existence of functional groups on nanoparticle surfaces is vital for their use as supports for bioactive component immobilization.…”

Mesoporous chitosan/activated charcoal powder and bead modified in 1‐butyl‐3‐methylimidazolium acetate for the adsorption of acid blue 25 from an aqueous solution

“…However, no significant difference was observed in the quantity adsorbed as the pH was raised from 8 to 12. The high quantity of AB25 dye adsorbed onto ChA and ChB at solution pH 2 was linked to the enhanced force of attraction between the negatively charged AB25 anionic dye and the positively charged surface of the adsorbents at lower pH values 43,48‐50 . The adsorbents’ hydroxyl and amino functional groups are protonated at lower solution pH values, facilitating better electrostatic attraction with the anionic AB25 dye.…”

Sieve-Like CNT Film Coupled with TiO2 Nanowire for High-Performance Continuous-Flow Photodegradation of Rhodamine B under Visible Light Irradiation

“…The emergence of continuous-flow devices opens an avenue to boost the prosperous development of successive batch manufacturing and has triggered a tremendous upsurge for the potential application in a variety of fields, such as chemical synthesis [ 1 ], mixture separation [ 2 ], pollutant treatment [ 3 ] and fuel cells [ 4 ], owing to the advantageous features of high efficiency, easy scalability, simple operation and low cost [ 5 , 6 ]. Of particular interest, the developing continuous-flow photoreactors, which use light for energy input, are increasingly appreciated as a reliable means to leap over the restrictions of traditional intermittent photocatalytic platforms and are regarded as a more promising strategy to carry out the photocatalytic removal of pollutants due to their continuity and sustainability [ 7 , 8 ].…”